fixed command line argument parsing bug

src/cats/command_line/command_line_options.c

@@ -289,8 +289,8 @@ struct program_options check_cats_main_arguments(int argc, char **argv)
                 exit_cats(EXIT_FAILURE);
         }
 
-        assert(optind < argc);
-        if (options.configuration_file == NULL && options.need_conf == true) {
+        assert(argc < 2 || optind < argc);
+        if (argc > 1 && options.configuration_file == NULL && options.need_conf == true) {
                 options.configuration_file = strdup(argv[optind]);
         }